Easy-opening closure

ABSTRACT

This disclosure describes a cap for use in closing the open end of a container. The cap is constructed of sheet material and is scored to form a tear portion at least partially removable from the cap. The cap has an end wall and a peripheral wall joined by a bend portion and the score is either discontinuous at the bend portion or of increased residual at the bend portion.

United States Patent Omar L. Brown Dayton, Ohio Aug. 22, 1969 Division of Ser. No. 714,989, Mar. 21, 1968.

Jan. 5, 1971 Erma! C. Frau Dayton, Ohio by mesne assignments inventor Appl. No. Filed Patented Assignee EASY-OPENING CLOSURE 11 Claims, 11 Drawing Figs.

U.S. Cl 113/121,

-1 13/15 int. Cl B2ld 51/00 Field of Search 113/121A,

[56] References Cited UNITED STATES PATENTS Primary Examiner-Charles W. Lanham Assistant Examiner-Michael J. Keenan Attorney-Smyth, Roston & Pavitt ABSTRACT: This disclosure describes a cap for use in closing the open end of a container. The cap is constructed of sheet material and is scored to form a tear portion at least partially removable from the cap. The cap has 'an end wall and a peripheral wall joined by a bend portion and the score is either discontinuous at the bend portion or of increased residual at the bend portion.

PATENTED JAN 51911 SHEET 1 OF 2 PATENTEU JAN 5197: 3,552,342

EASY-OPENING CLOSURE This application is a division of application Ser. No. 7l4,989, filed Mar. 21, 1968.

The easy-opening cap of this invention is particularly adapted for use as an outer cap of a dual cap closure assembly. A dual cap closure assembly is described in a copending application, Ser. No. 599,124, entitled Container End And Method Of Making Same, and fried on Dec. 5, 1966.

Dual cap closure assemblies typically include a metal outer cap and a plastic insert or inner cap within the outer cap or a sealing agent may be used in lieu of the plastic insert. The outer cap has a line of weakness therein forming a removable tear portion and a tab is attached to, or integral with, the tear portion for the purpose of removing the tear portion. With the tear portion removed, the entire outer cap can be removed and discarded, and thereafter, the inner cap alone is used as a removable closure element. This type of closure assembly can be used, for example, on a glass jar, bottle, or a special metal container and is particularly adapted for use on the container for a product which is not ordinarily entirely consumed shortly following the opening of the container.

' The outer cap of dual cap closure assemblies is typically constructed of sheet material and includes an end wall and a peripheral wall or flange extending transversely to the end wall and integrally joined thereto by a bend portion. The outer cap is scored to form a line of weakness which extends continuously from the peripheral wall over the end wall to define a removable tear portion. The tab for removal of the tear strip may be formed integrally with the outer cap or formed separately and then attached to the tear portion.

A very difficult problem arises in the scoring of the metal outer cap to form the tear portion. According to a prior art method, the scoring operation is carried out in the flat. That is, the closure blank is scored while the blank is in the flat condition and prior to the time that it is shaped or bent to form the peripheral walkThe line of score extends from the portion of the flat blank that will form the peripheral wall over a segment of the end wall to form the tear portion. Following thescoring operation, the blank is deformed or bent to convert a peripheral region of the blank into the peripheral wall and a central region of the blank into the peripheral wall and a central region of the blank into the end wall.

As the line of weakness extends from the peripheral wall continuously to the end wall, such deformation or bending also bends the material of the outer cap along the line of weakness. This bending of the prescored metal often results in frac- As the cap is weakened along the line of weakness, it deforms along the line of weakness under the influence of these forces and not infrequently completely fractures the material of the outer cap. Generally, the results of this prior art scoring operation is quite erratic and in some instances the squeezing together of the metal adjacent the bend portion along the line of weakness causes the edges of the tear strip to be overlapped by the adjacent portions of the outer cap. This captivates the tear portion and makes removal thereof much more difficult.

To avoid this problem it has been proposed to f rst convert the flat closure blank into a cap by bending a peripheral region thereof to form the peripheral wall. The scoring is then carried out after the cap has been formed. Although this solves the above noted problem. there are certain advantages to scoring the closure blank in the flat prior to formation of the cap. For

- example, by scoring in the flat, a single scoring tool may be it is desired to provide a method of making an easy opening cap of this type in which the scoring operation is carried out in the flat and which solves the problems heretofore experienced with the scoring of such caps in the flat.

Another problem with easy-opening caps of this type is that not infrequently the entire tear portion is torn from the outer cap thereby leaving two separate metal pieces which must be removed from the container to provide access to the opening thereof. This endangers the user because the portion of the cap remaining on the container has relatively sharp edges exposed'because of the removal of the tear portion and it is now quite difficult and dangerous to accomplish such removal. Accordingly, prevention of complete removal of the tear portion from the cap is highly desirable.

SUMMARY OF THE INVENTION The present invention permits scoring of the closure blank in the flat without any of the disadvantages heretofore experienced with scoring in the flat and then bending of the blank to form the cap. The present invention teaches carrying out the scoring operation in the flat to form two score line seg- 'ments while leaving a region of the sheet material intermediate the ends of the segments of greater thickness than the thickness of the sheet material along the segments. The blank is then converted into a cap by bending a peripheral region of ,the blank to convert the latter into a peripheral wall and to convert a central region of the blank into an end wall. The end wall and peripheral wall of the cap are joined by a bend portion which extends through the high residual region.

With this arrangement, the resulting article is a cap having a score line segment on the peripheral wall and a score line segment on the end wall with a region of the material of the bend portion between such segments being of greater thickness than the material along the score line segments. The region of greater thickness may be completely unscored. Alternatively, the region of the bend portion may be scored only slightly to thereby leave a higher residual than is present along the retaining portions of the score line. In either case, the region of the bend portion between the score line segments is sufficiently thick to avoid the problems noted above in connection with prior art methods.

To prevent the tear portion from separating completely from the remainder of the cap, the present invention teaches terminating the score line at one end on the end wall of the cap rather than on the peripheral wall as has been customary heretofore. By terminating the score line at one end on the end wall, there is a greater amount of metal to prevent complete tear-offof the tear portion.

Although exemplary embodiments of the invention have been shown and described, many changes, modifications, and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a flat section of sheet material after the same has been scored to form a tear portion partially removable therefrom.

FIG. 2 is a top plan view illustrating the completed outer closure cap.

FIG. 3 is an elevational view taken along line 3-3 of FIG. 2.

FIGS. 4 and 5 are enlarged fragmentary sectional views taken respectively along lines 4-4 and 5-5 in FIG. 3 and illustrating the score line adjacent the bend portion of the cap.

FIG. 6 illustrates typical scoring tooling for carrying out the scoring operation in a single step.

FIGS. 7 and 8 are enlarged fragmentary sectional views similar to FIGS. 4 and 5, respectively, and illustrating a second embodiment of the present invention.

FIG. 9 is a top plan view similar to FIG. 1 illustrating a third embodiment of the invention.

FIG. 10 is a top plan view of a completed outer cap.

FIG. 11 is an elevational view r10. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings and in particular to FIG. 1 thereof, reference numeral '11 designates a flat section of sheet material or a closure blank. The sheet material '11, in the embodiment illustrated, is in the form of a circular seg tnent of aluminum. A score line 13 which includes three score line seg ments 15, 17 and 19 are fo'rmedin the blank 11 to fo'rm-atear portion 21 which is partially removablefrom the remainderof the sheet material. The tear portion 21 may be of any suitable shape such as the shapes'illustrated in my copending Pat. application Ser. No. 599,I24. While the sheet material '11 is'still in the flat, a hollow rivet 23 is formed integrally with "the material of the tear portion 21 by an'ysuitable known method.

The score line segment 15 extends from the outerperiphery 25 generally radially inwardly toward a bend line or zone 27 and terminates prior to contacting'the bend line.'ln theform taken alongline -110 in shown in FIG. 1, the bend line 27 is-a preselected line about which the material of the blank 11 is bent .to form a cap '29, as shown in FIGS. 2 and 3.

' The score line segment 17 begins on the side of the bend line 27 opposite the score line segment and extendsfurther inwardly. Thus, both of thesegments15 and 17 are spaced from the bend line and are preferably generally aligned adjacent the bend line. The score line'segment 17 may extend over a'nyv suitable preselected area of the blank 11 but preferably extends over a substantial dimension of the blank. The other end of the segment 17 also terminates closely adjacent the bend line 27 in spaced relationship to a-confronting and aligned end portion of the score line'segment 119. To assist in preventing complete tear out of the tear portion 21 the outer end of the score line segment 19 is preferably in the form of a reverse bend 31, as illustrated.

'In the embodiment illustrated, the bend line 27 iscircular and concentric with the blank 11. The portion of theblank -11 lying outwardly of the bend line 27 constitutes a peripheral region 33 and a portion of a blank lying inwardly of the bend line may be defined as a central region 35. The bend linexextends between the score line segments 15,17 and 19 and none of the score lines crosses over the bend line 27. The rivet 23 may be -formed before, after, or simultaneously with the formationo'f the score line 13.

The next step of the method is to bend the peripheral region 35'about the bend line or zone 27 to form the cap shown in 'FIGS. 2 and 3. This bending operation, which'may becarried out with conventional tooling, converts the peripheral region '33 into a peripheral wall or flange 37 and converts the central region 35 into an end wall 39 with the'walls 37 and 39 being joined by a relatively small radius curved bend portion 41;

Either before or after the bending of the blank '11 about the bend line 27, a tab-43 or other suitable pull member is affixed .to the tear portion 21. In the embodiment illustrated, the tab 43 is a ring tab and is secured to the tear portion2l by staking of the hollow rivet 23.

With reference to FIG. 4, it can be seen that the score lin segments 15 and 17 leave thin residual webs '45 and 47, respectively, which extend toward the 'bend portion 41 and terminate closely adjacent thereto. The webs 45 and47'a're "spaced by a region 49 of the bend portion 41. The region 49,

in the embodiment shown in FIGS. 1-6, is significantly.

thicker than either of the webs 45'and 47 and is not scored. Consequently, the bending of the material of the blank'll about the bend line 27 causes no disruption of the score line at the bend line 27 because no score line crosses such bend'line. The precise point for stopping the score line segments 15 and 17 will depend upon several factors. First, the score lines 15 and 17 should be sufficiently close together so that the failure 1 to score'through the region 49 will not unduly impede removal of the tear portion 21 and so that tearing of the score line 13 will continue smoothly from the segment 17 to the segment I region-53is similar to the region v 7 either of 'th'ewebs-47 or 51and is not scored. Thus, thebe nding-aboutthebendiline 27 can be ca a ing ofthezscore-line 13. -'A;lower periph container-(not shown-)as-a single unit.

{15. The score-linesegments 15-and1'7may extend somewhat into the bend portion 41 :"ho'wever, they Fshould not extend completelyafcross 'the ben'd portion! or extendinto the bend portion-a sufficient distance to cause rupture ofthe material during'ithe bendingopera'tion orcaptiv 21. Y

f 'Similarly, the score line segment i19' defines;aresidual web 51 as shown in FIG. '5 which is' s pac' the other end of the residualweb 47 by region 53 ebendportion 41. The in thatit is thickerthan tear portion out withoufdi'stortportion-bf theeap is 'tur'ne'dupw'a'rdly to'f'orma bead'5'5. I

The easy-opening cap 29-can 'be'operated a conventional 'manner'by'fir'stpivoting of the tab 43 to initiate rupture of the score the region intermediate,the-iscore line segments 15 and 17'and 17 3116 19. U 4 v I 'FIGS. 7 and 8 illustrate a modification of the present invention'in which part's'cor'respond g' to'portions of th'e'embodi- 'ment of FIGS. I Saredesignated byeorresponding primed reference CharacterSJIn'the form shown in FIGS. 7 and 8,'a reg'ion49 of 'the'bend portion 41"hasfascore line segmenti6l which interconnects the score linesegments 15 andl7. The

thickness ofthe material along the score. line segment 61 is thicker, however, .than the thicknesstof the residual webs and-47 which'is tosaythatthe residual, webs 45' along the score line segment 61 is thicker, however, than the thickness is higher'than the residual along'the score line segments 'IS'and 17'. In'actual practiceof the invention, the score line 61 may. beonly a few. thousandth deepand in no event of sufficient depth to permit fracture therealong during the bending operation or captivation of the tear portion- FIG. 8 is similar in illustrating a score line segment 63 which extends across the bendportion 41. to interconnect score line segments 17" and 19' The thickness of the material along the score line 63 is greater than the thickness of thematerial of the residual webs 47 and '51. In all other respects, the'embodiment shown in FIGSI7 and 8 is identical'to the embodiment shown in FIGS. l"5.

FIGS. 9--11'illustrate a third form of the invention which is directed to preventing complete-tear out of the tear portion. FIG. 9 illustrates a'blank 65which is identical to the blank 11 in every respect except 'as" specifically noted herein. The blank 65 has score line'segment 67 and 69formed therein to define a "tear portion71'which is partially removable from the blank '65. The segment 67 is aligned with the segment '69 and. is spaced'there'fromto avoid extending .across a bend line 73...

' The'score line segment 67 preferably extends all the way to an.

end wall 83 and there is no'score line segment corresponding outer edge 75 'of the blank 65. One end of the score line segment 69 terminates adjacent the bend line 73 and the segment 67 and the other end of the score line segment 69 terminatesclosely-adjace'nt the bend-line 73and on the inner side thereof. A hollow rivet 79'is suitably formed at one end of the tear por tion'71. 7

Next, the material of the blank 65 is bent about the bend line 73 to form-a cap 81 shown-in FIGS. 10 and 1 1. The cap8 l has an end wall83 and a peripheral wall 85 joined to the end v wall by abend portion 87. The-score line segment 67 does'not extend across the bendportion87 and appears substantially as shown in FIG. 4. The score line segment 69 terminates on the to the score line segment 71 of FIG. 1. At any suitable time,

either before or after the bending operation, a tab 89 can be suitably secured to the tear portion 71 as by staking of the hollow rivet 7 9. 4 I

It can be seen, therefore, that the embodiment of FIGS. 9- 11 also avoids crossing-of the bend portion 87 with a score line. Furthermore, the termination of the score line'69 on the end wall 83 rather than on the peripheralwall 85, provides additional material for resisting complete severance and separation of the tear portion 71 from the remainder of the cap 81. A bead 88 may be formed by rolling a peripheral portion of the p vpwardly- Although exemplary embodiments of the invention have been shown and described,many changes, modifications, and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of this invention.

1. ln a method of making an easy-opening cap from a section of sheet material, the steps of: 1 j

scoring the sheet material to define a firstresidual web extending from a first location at an outer region of thesection of sheet material generally inwardly toJa second location; 1 v v scoring the sheet material to define a second residual web extending from a third location whichis spaced inwardly from said second location to at least partially define along with said first web a tear portion at least partially removable from the section of sheet material;

leaving said residual webs spaced by a region of sheet material of'greater thickness than the thickness of the adjacent portions of said residual webs; and I bending a peripheral region of the section of sheetmaterial along a preselected zone which extends between said second and third locations to convert said section of sheet material into a cap having an end wall and a peripheral wall joined along a bend line with said first and second residual webs lying on said peripheral wall and said end wall, respectively, and being separated by said region of sheet material, said step of bending being carried out after said steps of scoring.

2. A methodas set forth in claim 1. including the step of scoring said region to form a third residual web of greater thickness than the first and second webs and extending between said first and second webs. I

3. A method as-defined in claim 1 wherein said steps of scoring are carried out simultaneously.

4. .In a method of making an easy-opening cap from a generally flat section of sheet material wherein the section of sheet material is bendable about a preselected zone to convert the section of sheet material into a cap having an end wall and a peripheral wall, the steps of: v

scoring the sheet material to define first and second rup turable residual webs with the first residual web extending from a location adjacent the periphery of the section of sheet material generally inwardly to a first location adjacent the zone and with the second residual web extend ing from a second location on the other side of the zone and adjacent said first location generally inwardly to at least partially define along with said first'residual web a tear portion at least partially removable from the section of sheet material; leaving a region of sheet material extending across said zone and joining said first and second residual webs of greater thickness than either of said first and second residual webs; and r a bending the section of sheet material along said zone subsequent to said step of scoring toconvert the section of sheet material into a cap having an end wall and a peripheral wall joined by a bend portion and to convert said region of said material into a portion of said bend portion joining said first and second residual webs. 5. A method as defined in claim' 1 including the step of leaving said re ion of sheetmaterial unscored.

6. A me hod of making an article of sheet material having a substantially continuous line of weakness and a bend portion comprising:

providingasection of sheet material with a portion of said section being substantially flat;

scoring said portion of said section to form a first elongated residual web which terminates at one end at a first location;

scoring said portion of said section to form a second elongated residual web which terminates at one end at a second location-which is closely adjacent said first location; leaving said locations spaced by a region of sheet material of greater thickness than the thickness of said residual webs at said locations; and I A bending said zone of sheet material subsequent to said steps of scoring. along a preselected zone which extends through said regions.

7. A method of making an easy opening cap from sheet material comprising scoring the sheet material to define a first line of weakness extending from a first location on the sheet material to a second location on the sheet material; scoring the sheet material to define a second line of weakness extending along a predetermined path from a third location to at least partially define along with said first line of weakness a tear portion at least partially removable from the sheet material, said third location being adjacent said second location; leaving said lines of weakness spaced by a region of sheet material of greater thickness than the thickness of the sheet material at said second and third locations; and

bending subsequent to said steps of scoring the sheet material along a preselected zone which extends between said second and third locations to form a cap having an end wall and a peripheral wall joined along a bend line with said first and second lines of weakness lying on said peripheral wall and said end wall, respectively, and being separated by said region of sheet material.

8. A method as defined in claim 7 wherein said first and second lines of weakness define first and second imperforate, rupturable, residual webs, respectively.

9. A method as defined in claim 8 wherein the sheet material is'substantially fiat when said steps of scoring are carried out.

10. A method of making a closure cap from sheet material 5 comprising:

scoring the sheet material to define a first rupturable residual web terminating at one end at a first location;

scoring the sheet material to define a second rupturable residual web extending from a second location over a preselected region of the sheet material, said first location being adjacent said second location;

scoring the sheet material to define a third rupturable residual web extending between said first and second locations with the thickness of said third rupturable residual web being greater than the thickness of at least one of said-first and second rupturable residual webs, said rupturable residual webs at leastpartially defining a tear portion at least partially removable from the sheet material; and

bending the sheet material along a bend region and through said third rupturable residual web subsequent to all of said steps of scoring .to form a closure cap having a peripheral wall and an end wall joined along said bend regionwith said first and second rupturable residual webs lying on said peripheral wall and said end wall, respective 'ly, and with said third rupturable residual web extending across said bend region.

11. A method as defined in claim 10 wherein said one rupturable residual web is said firstrupturable residual web. 

1. In a method of making an easy opening cap from a section of sheet material, the steps of: scoring the sheet material to define a first residual web extending from a first location at an outer region of the section of sheet material generally inwardly to a second location; scoring the sheet material to define a second residual web extending from a third location which is spaced inwardly from said second location to at least partially define along with said first web a tear portion at least partially removable from the section of sheet material; leaving said residual webs spaced by a region of sheet material of greater thickness than the thickness of the adjacent portions of said residual webs; and bending a peripheral region of the section of sheet material along a preselected zone which extends between said second and third locations to convert said section of sheet material into a cap having an end wall and a peripheral wall joined along a bend line with said first and second residual webs lying on said peripheral wall and said end wall, respectively, and being separated by said region of sheet material, said step of bending being carried out after said steps of scoring.
 2. A method as set forth in claim 1 including the step of scoring said region to form a third residual web of greater thickness than the first and second webs and extending between said first and second webs.
 3. A method as defined in claim 1 wherein said steps of scoring are carried out simultaneously.
 4. In a method of making an easy-opening cap from a generally flat section of sheet material wherein the section of sheet material is bendable about a preselected zone to convert the section of sheet material into a cap having an end wall and a peripheral wall, the steps of: scoring the sheet material to define first and second rupturable residual webs with the first residual web extending from a location adjacent the periphery of the section of sheet material generally inwardly to a first location adjacent the zone and with the second residual web extending from a second location on the other side of the zone and adjacent said first location generally inwardly to at least partially define along with said first residual web a tear portion at least partially removable from the section of sheet material; leaving a region of sheet material extending across said zone and joining said first and second residual webs of greater thickness than either of said first and second residual webs; and bending the section of sheet material along said zone subsequent to said step of scoring to convert the section of sheet material into a cap having an end wall and a peripheral wall joined by a bend portion and to convert said region of said material into a portion of said bend portion joining said first and second residual webs.
 5. A method as defined in claim 1 including the step of leaving said region of sheet material unscored.
 6. A method of making an article of sheet material having a substantially continuous line of weakness and a bend portion comprising: providing a section of sheet material with a portion of said section being substantially flat; scoring said portion of said section to form a first elongated residual web which terminates at one end at a first location; scoring said portion of said section to form a second elongated residual web which terminates at one end at a second location which is closely adjacent said first location; leaving said locations spaced by a region of sheet material of greater thickness than the thickness of said residual webs at said locations; and bending said zone of sheet material subsequent to said steps of scoring along a preselected zone which extends through said regions.
 7. A method of making an easy opening cap from sheet material comprising scoring the sheet material to define a first line of weakness extending from a first location on the sheet material to a second location on the sheet material; scoring the sheet material to define a second line of weakness extending along a predetermined path from a third location to at least partially define along with said first line of weakness a tear portion at least partially removable from the sheet material, said third location being adjacent said second location; leaving said lines of weakness spaced by a region of sheet material of greater thickness than the thickness of the sheet material at said second and third locations; and bending subsequent to said steps of scoring the sheet material along a preselected zone which extends between said second and third locations to form a cap having an end wall and a peripheral wall joined along a bend line with said first and second lines of weakness lying on said peripheral wall and said end wall, respectively, and being separated by said region of sheet material.
 8. A method as defined in claim 7 wherein said first and second lines of weakness define first and second imperforate, rupturable, residual webs, respectively.
 9. A method as defined in claim 8 wherein the sheet material is substantially flat when said steps of scoring aRe carried out.
 10. A method of making a closure cap from sheet material s comprising: scoring the sheet material to define a first rupturable residual web terminating at one end at a first location; scoring the sheet material to define a second rupturable residual web extending from a second location over a preselected region of the sheet material, said first location being adjacent said second location; scoring the sheet material to define a third rupturable residual web extending between said first and second locations with the thickness of said third rupturable residual web being greater than the thickness of at least one of said first and second rupturable residual webs, said rupturable residual webs at least partially defining a tear portion at least partially removable from the sheet material; and bending the sheet material along a bend region and through said third rupturable residual web subsequent to all of said steps of scoring to form a closure cap having a peripheral wall and an end wall joined along said bend region with said first and second rupturable residual webs lying on said peripheral wall and said end wall, respectively, and with said third rupturable residual web extending across said bend region.
 11. A method as defined in claim 10 wherein said one rupturable residual web is said first rupturable residual web. 